In FIGS. 4 (a) and (b), a fusible link unit disclosed in JP-A-2001-297683 (hereinafter PTL1) is connected to a battery of a motor vehicle to supply electric power to a load. The fusible link unit includes a conductive bus-bar 3 including a plurality of fusible portions 2 (2a, 2b to 2e), resin housings 4, 5 which are molded integrally with the bus-bar 3 in predetermined positions thereon and transparent resin covers 6, 7 which are locked on the resin housings 4, 5.
As portions of the bus-bar 3 that are exposed from the resin housing 4, there is a battery terminal connecting portion 8 which connects to a battery terminal, not shown, an electric wire connecting portion 10 in which a bolt 9 is provided for connection with a terminal of an end of an electric wire, not shown, and the fusible portion 2a. As portions of the bus-bar 3 which are exposed from the resin housing 5, there are the respective fusible portions 2b to 2e and a plurality of tab terminals 11 which connect to the load. As an additional exposed portion, there is a hinge portion denoted by reference numeral 12. The hinge portion 12 is formed as a portion which is to be folded in the position where it is provided.
The resin housings 4, 5 have exposing window portions 13, 14 for exposing the fusible portions 2a to 2e. The exposing window portion 13 is formed so as to allow the fusible portion 2a to be faced visibly from front and rear directions of the resin housing 4. The exposing window portion 14 is formed so as to allow the fusible portions 2b to 2e to be faced visibly from front and rear directions of the resin housing 5. These exposing window portions 13, 14 are designed to be covered with the transparent resin covers 6, 7. Locking the transparent resin covers 6, 7 on the exposing window portions 13, 14 is effected by locking projections and locking portions which are hooked on the locking projections.
Since locking the transparent resin covers 6, 7 on the exposing window portions 13, 14 is not specifically depicted in FIGS. 4(a) and (b), a complementary description will be made below by reference to FIG. 5.
Substantially claw-shaped locking projections 16 are formed at longitudinal side portions (only one of which is shown in FIG. 5) of an exposing window portion 15. A substantially frame-shaped locking portion 18 is formed at each of longitudinal side portions (only one of which is shown in FIG. 5) of a transparent resin cover 17 which covers the exposing window portion 15 described above. In this configuration, in covering the exposing window portion 15 with the transparent resin covers 17, when the locking portions 18 of the transparent resin covers 17 ride over the locking projections 16 of the exposing window portion 15 to thereby be hooked on the corresponding locking projections 16, the transparent resin covers 17 are locked on the exposing window portion 15 by the hook-like engagement of the locking portions 18 with the locking projections 16.